1. Field of the Invention
Apparatuses and methods consistent with the present invention relate to a key input device combined with a key display unit and a digital appliance having the same.
2. Description of the Prior Art
A keypad is an important input device in digital appliances. In order to efficiently provide functions of digital appliances such as mobile phones, remote controllers, personal digital assistants (PDAs), handheld personal computers (HPCs), and notebook computers, the configuration of the keypad and how to position keys on the keypad have been studied in terms of ergonomics.
Although input of specified functions has been considered in terms of ergonomics, the position of the keypad, functional keys and images have not allowed for optimal arrangement. For example, a keypad designed for a right-handed person may not be useful for a left-handed person. Further, a keypad designed to orient a character input may not be useful for cases where numerals or special characters are frequently inputted.
FIG. 1 is an exemplary view of a related art soft key embodied through a display window in which characters representing keys are varied in accordance with functions of the keys.
Korean Patent Unexamined Publication No. 10-2004-59496 discloses a soft key in which functions of some keypads are varied in accordance with specified functions. This soft key provides functions similar to those of the soft key of FIG. 1. A mobile phone 1000 includes display screens 11 and 12 and keypads 110 and 120. The keypad 110 positioned just below the display screen provides a variable key function. The variable key function means that a key has different functions according to selected function modes. For example, FIG. 1a shows the case of using a telephone directory where “Delete”, “Select”, and “Correct” functions, which are suitable when using the telephone directory, are mapped on keys in the keypad 110. In order to display the functions mapped on the key, the corresponding functions are shown on the display screen 12. FIG. 1b shows the case of using a short messaging system (SMS) function where “Cancel”, “Send”, and “Recipient” functions, which are required to edit messages to be sent, are mapped on the keys in the keypad 110. In order to display the functions mapped on the keys, the corresponding functions are shown on the display screen 12.
The mobile phone shown in FIG. 1 includes functions provided by some keys and varied in accordance with a selected application, and uses one small window to show the variable functions when the corresponding applications operate.
In using such a small window, however, since the functions are not directly marked on the keys or buttons, it is difficult for a user to perceive the functions. Further, the key set according to the applications are not changeable, which is inconvenient for a user.
Therefore, an apparatus whereby a user can freely set the functions of keys is required. Further, an apparatus for enabling the user to freely use the keys is required since the user cannot freely represent the character or image to identify the function of a key or the key itself. Accordingly, an apparatus and method capable of displaying the information that is indicative of the function of the corresponding key directly on the key is required.